Up to the point I did, I found Spirit Kings the hardest if it's not outgeared. HC Amber Shaper is unforgiving as hell, but not hard per say. I have yet to see Shek'zeer, Protectors, Tsulong and Sha on HC.

Heroic Sha of Fear was far from the hardest. Not really too much to learn, only difficult part was keeping focused for 20 minutes. Also Heroic Empress was a joke with Disc Priests. My vote is Heroic Tsulong (post cheese nerfs) or Heroic Amber-shaper because people suck at hitting buttons at the right time.

Sha is the hardest to get the first kill. Really easy to repeat since mechanics wise it is easy and very little RNG. Tsulong sucks because it is so RNG filled.

Originally Posted by Runewrath

Heroic Sha of Fear was far from the hardest. Not really too much to learn, only difficult part was keeping focused for 20 minutes. Also Heroic Empress was a joke with Disc Priests. My vote is Heroic Tsulong (post cheese nerfs) or Heroic Amber-shaper because people suck at hitting buttons at the right time.